Breech block buffer

ABSTRACT

An automatic firearm incorporates a shock absorber in which a buffer spring is accommodated in a bore in the breech block and bears at one end against a buffer member which is supported by means of a slider to which the buffer movement is imparted and which extends transversely to the direction of movement of the buffer member and is accommodated in a slot in said member. Preferably the buffer spring encloses a striker pin the end of which is exposed in the slot and adapted for operation by a hammer for initiating firing of the weapon.

United States Patent 1 Miiller et al.

[ July 31, 1973 BREECH BLOCK BUFFER [75] Inventors: Tilo Miiller, Oberndorf; Dieter Ketterer, Oberndorf/Neckar, both of Germany [73] Assignees Heckler & Koch GmbH,

[30] Foreign Application Priority Data FOREIGN PATENTS OR APPLICATIONS 944,776 6/l956 Germany 89/198 Primary Examiner-Stephen C. Bentley Attorney-Craig, Antonelli and Hill [5 7] ABSTRACT An automatic firearm incorporates a shock absorber in which a buffer spring is accommodated in a bore in the breech block and bears at one end against a buffer member which is supported by means of a slider to May 15, Germany P the bu -er mo e s imparted and ex tends transversely to the direction of movement of the 2% F' ?g ?g buffer member and is accommodated in a slot in said 5 'f 89 2 member. Preferably the buffer spring encloses a stn'ker 1 0 l pin the end of which is exposed in the slot and adapted References Cited fwoeraggiratron by a hammer for Initiating firing of the UNITED STATES PATENTS 2,900,877 8/1959 McClenahan 89/198 3 Chin, 3 9mm! 8" t if /Z J m I 1;

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4 221 I e N INVENTORS Tu o MBLLER ND D\ETER KETTERER BY m Hm 3f AKSUL ATTORNEYS BREECIHI BLOCK BUFFER The invention relates to automatic firearms, especially a breech block for automatic firearms such as an automatic rifle with a shock absorber device which comprises a buffer spring arranged in a bore of the breech block member and a buffer member guided and held in the bore, resting against the buffer spring and projecting out of the rear end of the breech block.

It is known from German specification No. 944,776 to hold a hollow buffer member by means of a pin which traverses the buffer member and the buffer spring concentrically and the end of which is screwed into the block breech. Thereby the pin rests by a head thereof against a shoulder within the buffer member. Then the pin substantially fills the bore of the buffer member as well as the space surrounded by the spring.

This known arrangement has the disadvantage that the spring must be made substantially shorter than the block breech since sufficient space is required in addition to the spring for a threaded bore for screwing in the holding pin. This bore must have a substantial length if the pin is to seat therein with the necessary strength. This space is not, however, available in many cases since the length of the breech block is of direct influence on the length of the weapon casing so that the arrangement of a buffer device in the breech block has not heretofore been found practicable.

The invention is directed to the problem of avoiding this disadvantage of the known breech block with a buffer device and so to construct the buffer device that the length of the breech block need not be substantially increased for installation thereof.

This problem is solved according to the invention by the fact that the buffer member is held by a slider which is inserted in the breech block transversely to the direction of movement of the buffer member and traverses a slot in the buffer member. Such slider has no greater space requirement in the longitudinal direction of the breech than the head at the end of the pin with the known breech block so that the additional space which is required with the known breech block for the screw thread for screwing in the pin is completely saved by the invention. Thereby the invention permits the use of a buffer device in the breech block even if insufficient space is available for a buffer device such as is provided with the known breech block.

As above stated with the known breech block the buffer device is supported by a pin which substantially completely fills the space surrounded by the spring. It is therefore necessary to provide a special bore for this buffer device which must be provided parallel to the bore required for the striker pin. Therefore the known arrangement is only applicable where the crosssectional dimensions of the breech block are sufficiently great to permit such parallel bores. In contrast thereto the invention permits the buffer spring to be ar ranged in the same bore as the striker pin so that it surrounds the striker pin. The invention therefore permits a buffer device to be included in the breech block even if the cross-sectional dimensions thereof are relatively small and nevertheless a bore of substantial size is to be provided for the buffer device which permits the mounting of a powerful buffer spring.

In a preferred embodiment of the invention in which the striker pin is loaded in known manner by a coil compression spring which tends to hold the striker pin in a rear position, the rear end of the striker pin engages a bore in the slider in this rear position and thereby retains the slider in a simple way in its position of use. This embodiment of the invention is also particularly appropriate in cases in which the breech block is intended for firearms with hammer firing since then the rear end of the striker pin traverses the slider and can then be accessible for the hammer.

In this case the slot in the buffer member can be open to the rear so that the end of the buffer member projecting from the breech block forms a notch surrounding the rear end of the striker pin. The hammer can then engage in the open end of the fork on striking the rear end of the striker pin.

Further details and arrangements of the invention can be seen from the following description in which the invention is further described and explained on the basis of the constructional example shown on the drawing. The features described and shown can be applied individually on their own or several of them may be applied in desired combination. In the drawings:

FIG. 1 is a longitudinal section through the breech block carrier and the rear portion of the breech block head of a breech block according to the invention,

FIG. 2 is a section on the line II-ll through the rear portion of the breech according to FIG. 1,

FIG. 3 is a view of the breech according to FIG. 1 in the direction of the arrow III.

The breech shown in the drawing consists of a breech carrier 1 and a breech head 2, which are connected together by means of a control member 3 engaging in the breech block carrier l and in the breech block head 2. Moreover a pawl serves to secure the breech block carrier ii and the breech block head 2 together.

The breech block carrier 1 embodies a rearwardly open longitudinal bore 11 in which two coil compression springs 12 and 13 are inserted axially one behind the other and the turns of which bear on the inner wall of the bore Ill. The forward coil compression spring 12 rests at one end face 14 at the end of the bore Ill while the end of the second coil compression spring 13 remote from the spring 12 bears on a buffer member 15 which is inserted in the outer end of the bore Ill and embodies a projection 16 engaging concentrically in the second coil spring 13.

The rear end of the buffer member 13 projecting out of the breech block carrier I is provided with a longitudinal slot 17 which extends nearly to the rear end of the rear coil compression spring 13 so that the rear end of the buffer member forms a fork 18. The buffer member 15 is held in the breech block by a slider member 19 which is inserted perpendicularly to the axis of the ion gitudinal bore ill and thus perpendicularly to the direction of movement of the buffer member 15 in a corre sponding groove 20 of the breech block carrier l.

The striker pin 21 is arranged in the longitudinal bore ill as well as the coil compression springs I2 and i3 and the buffer member 115. Its forward end traverses a corresponding bore in the control member 3 while its rear end engages a corresponding bore in the buffer member 15 and also traverses a bore in the slider 19 by means of an extension pin 22 of reduced diameter. The striker pin 21 is loaded by means of a coiled compression spring 23 arranged concentrically on it which bears on the one hand at the rear end of the control member 3 and on the other hand against a shoulder 24 which is arranged about the center of the striker pin 21 and therefore tends to press the striker pin 21 rearwardly and thereby to hold the extension pin 22 in the bore of the slider 19. Consequently the slider member 19 is locked by means of the striker pin 21 in the groove 20 of the breech block carrier 1. Furthermore, the rear end 22 of the striker pin 21 is accessible to a hammer in the longitudinal slot 17 of the buffer member so that the breech block, shown as one constructional example, is suitable for automatic weapons with hammer firing.

The drawing makes it clear that for the coiled springs 12 and 13 serving as buffer springs no substantial additional space is required in the breech block carrier 1 and these buffer springs can have practically the whole length of the breech carrier. For strengthening the buffer effect in the constructional example shown braking rings 25 are provided between the turns of the rear buffer spring 13 which are forced in known manner against the innter surfaces of the longitudinal bore 11 and thereby exert a strong retardation, if the buffer member 15 is driven on rebound against a rear bearing face in the breech carrier 1.

Henceby the invention a breech block with a built-in shock absorber device is provided in which practically no additional space is required for the buffer device and which is, moreover, particularly simple to produce and assemble.

If the breech block is to be taken apart for servicing it is sufficient to depress the striker pin so far rearwardly into the breech block carrier 1 by means of a pin or the like until the slider member 19 is freed and then can be withdrawn from the breech block carrier. After removal of the slider member 19 not only is the buffer device with the buffer member 15, the buffer springs 12 and 13 and the braking rings 25 released but also the striker pin 21 with the coil spring 23 loading it can be withdrawn from the breech block. The invention is applicable to all types of breech-breech block arrangements especially also inertia breech blocks with closure firing. With such breech blocks it is then not necessary that the rear end of the striker pin should be accessible so that it is sufficient if a slot is present in the buffer member which need not be open at its rear end. Thus also the positioning of this slot in reference to the striker device of the weapon in which such a breech block is to be used is without significance while with the breech block shown the slot 17 must naturally lie in a plane in which the hammer movement'is effected. It is also possible to provide other locking means for the slider if retention of the slider member by means of the striker pin is not possible which may be the case for example with breech blocks in which the striker pin is caught in a tensioned position on the forward movement of the breech block. I

What we claim is:

l. Breech block for automatic firearms comprising a buffer spring arranged in a bore of the breech block, the buffer spring surrounding a striker pin, a buffer member guided and held in the bore, said buffer member being supported against the buffer spring and projecting from the rear end of the breech block, a slider member is inserted into the breech block transversely to the direction of movement of the buffer member and traversing a slot in the buffer member, said slider member being in bearing engagement with the breech block.

2. Breech block according to claim 1, characterised in that the striker pin is loaded by means of a coiled compression spring which tends to hold the striker pin in a rearward position and that the rear end of the striker pin engages in this rearward position in a bore of the slider member.

3. Breech block according to claim 1, characterised in that a longitudinal slot in the buffer member is rearwardly open so that the end of the buffer member projecting from the breech block forms a fork surrounding the rear end of the striker pin.

' l III I 

1. Breech block for automatic firearms comprising a buffer spring arranged in a bore of the breech block, the buffer spring surrounding a striker pin, a buffer member guided and held in the bore, said buffer member being supported against the buffer spring and projecting from the rear end of the breech block, a slider member is inserted into the breech block transversely to the direction of movement of the buffer member and traversing a slot in the buffer member, said slider member being in bearing engagement with the breech block.
 2. Breech block according to claim 1, characterised in that the striker pin is loaded by means of a coiled compression spring which tends to hold the striker pin in a rearward position and that the rear end of the striker pin engages in this rearward position in a bore of the slider member.
 3. Breech block according to claim 1, characterised in that a longitudinal slot in the buffer member is rearwardly open so that the end of the buffer member projecting from the breech block forms a fork surrounding the rear end of the striker pin. 